Permanent mold construction



ma. 28, w26. 1,612,133 H. s LEE PERMANEN'LQMOLEV- CONSTRUCTION Filed Feb, 13, 1925 Patented Dec. 28, 1926.

Unirse stares PATENT t' F l t@ HARRY s. Las, or PLYMOUTH, MICHIGAN;

PERMANENT MOLD CONSTRUCTION.

Application filed February l This invention relates to permanent mold construction and has for its object the means for varying the size of the mold cavity for casting any desired size of casting with the same mold. The specific mold here illus- Jtrated shows molds tor casting window weights but obviously' this same principle of varying the size of the mold cavity could be applied to the molds for casting different articles. i

Another object ot the invention is the provision of means for casting a hole through the casting by using a core which may be automatically retracted so as to permit the castin to be discharged from the mold.

Int e drawings:

Figl is an elevation of a mold.

Fig. 2 is an elevation of the mold showing the opposite side from that shown in Fig. 1.

Fig. 3 is a section taken on the line 3-3 of Fig. 1, showing the retractable cores.

Fig. 4 is a section on the line 4 4 'of Fig. 2, showing the adjustable inserts for varying the size ot the mold cavity.

In the illustration, I have illustrated only half ofthe mold, but of course it is understood that to complete tlie mold there is another half identical with the one illustrated which is adapted to mate with lthis mold halt and is constructed in exactly the same way and contains the same adjustable inserts and retractable cores which are actuated and secured to the mold in the same manner.

The mold half illustrated comprises' preferably a gray iron casting designated a. It is provided with one or more molding cavities Z), which are here shown as elongated cavities for casting the ordinary window weight, with which we are all familiar. The walls ot the cavity are provided with a plurality of .tapped holes c and the inserts d are arranged' to fit within the mold cavity and the bolt or set screw e is screwed into the tapped hole and into the insert tor securing the same in place. As shown in Figs. 2 and 4., this insert is shown secured in theI molding cavity and materially shortcns the length of the same so that when the casting is poured a shorter window weight may be formed than would be formed it the inserts were left out. 'Ihe tapped hole o when not in use may be plugged up with the short studs f so as to prevent the molten metal from leaking out.

'Ihe size ot' the mold cavity can be varied by securing the inserts in any one ot a plie 4length than the one that is illustrated by the solid lines. Obviously both ot-these methods could be employed whenever desired.

f In casting a Window weight, it is neces sary to cast a hole lthrough the same, but

.obviously a core must be. provided which may be easily retracted or knocked out so as to permit the casting to be discharged from the mold. It is the usual practice to make a sand core which may be knocked out of the casting after the same has been discharged, but these sand cores entail a great deal of labor in making the same and necessitates the placing of a new core at every casting operation.

To overcome this difficulty, I provide the retractable core h which is supported in the recess a' in the mold. This core or pin h is provided with a reduced portion j which is projected' out of the back of the mold, the reduced portion forming a shoulder 7c which is arranged to abut the bottom ot the recess e' so as to limit the retracting movement ot the core. The drawings illustrate a pair ot mold cavities, but obviously one mold could be used in a mold but it is more practical to cast a pair ot window weights simultane ously. Because of this I show a pair ot cores L which are bridged at their tree ends by a connecting bracket m. This bracket m is secured b v means ot the pins nto the. reduced portion ot said cores. and supports a roller 0 which is arranged to engage a cam p as shown in Fig. 3, so that as the mold moves by the cam the cam presses the cores inwardly the desired distance until the cores carried b v one mold halt abut the cores carried by the other halt. Springs r surround the reduced end portion oi" the core and exert` an outward pressure on the same for holding the core in a retracted position, forcingr the shoulder 7c up against the hottom of the recess '5. s the roller o rides oft' the cam it allows thecores to be forced out wardly under the spring power and to be retracted within the recess, whereupon the mold halves may be separated automatically or by hand, thus permitting the casting to be discharged from the mold.

When using permanent molds such as illustrated in the drawings, in a permanent mold machine, it is obviously an advantage to have cores which may be automatically retracted and projected from and into the molding cavity at the proper time sonas to eliminate as much as possible of the human element. l This rovides more uniform castings and also ehminates considerable of the labor costs in large production.

What I claim is:

1. In a mold for casting metals, the combination of a mold having a permanent molding cavity adapted to receive molten metal and impart a finished contour thereto, an insert adapted to be positioned in said molding cavity, and means for removably securing the insert to the normal molding.

cavity "at various points to vary the size of said cavity.

2. Ina mold for casting metals, the combination of a mold having a normal molding cavity ada ted to impart a finished contour to the article cast, an insert lshaped to fit 'Within said finished cavity, and means for removably securing said insert at various points in said cavity to vary the size of said molding cavity to replace part of the normal nished contour of said molding cavity.

3. In a mold for casting metals, the combination of a mold having a normal molding cavity adapted to impart a linished contour to the article cast, and a removable insert secured in said molding cavity at various points for adj ustably reducing the size thereof and to permit the increasing or decreasing of the size of said molding cavity by securing smaller, or larger, inserts therein.

4. A mold for casting metals, comprising in combination a permanent molding cavity adapted to impart a finished contour to the article cast therein, means insertable` Within said permanent cavity to reduce the size thereof and to form a temporary molding cavity of different size or shape, and retractable means for forming an impression in the casting independently ofthe use of said normal cavity or temporary cavity.

In testimony whereof I have alixed my signature.

HARRY S. LEE. 

